Have you checked under the face plate to see if anything is amiss there? Might be a long shot but I would look.
I would want to be as certain as I could be that it was a mechanical problem and not a cleaning problem. If it was my machine I would be spraying kerosene or some kerosene cleaner in the oil holes and on all moving metal on metal spots I could identify. If this didn't fix it then I would have to look at isolating the top main shaft from the bottom main shaft, which means disconnecting the rod running through the pillar. I've not done this on a 201, only on machines with a removable top cover. Disconnecting the top from the bottom would allow you to pin down which isn't moving freely. This would be fairly involved and others may have better ideas or warnings as to not trying this.